class_docstr: All converters should inherit from this class.
  
  Attributes:
    ctx: EntityContext
code: def visit(self, node):
      if not self._ast_depth:
          if self._used:
              raise ValueError("converter objects cannot be reused")
          self._used = True
  
      self._ast_depth += 1
      try:
          return super(Base, self).visit(node)
      finally:
          self._ast_depth -= 1
  
imports: import enum
  from tensorflow.python.autograph.pyct import anno
  from tensorflow.python.autograph.pyct import ast_util
  from tensorflow.python.autograph.pyct import parser
  from tensorflow.python.autograph.pyct import templates
  from tensorflow.python.autograph.pyct import transformer
  from tensorflow.python.util.tf_export import tf_export
label_desc: Use image node_id 3 for calling the Base obj's underlying member method code with example usage: obj.visit(node) and returns: super